Fission of opinions in subjective logic

Opinion fusion in subjective logic consists of combining separate observers' opinions about the same frame of discernment. The principle of fission is the opposite of fusion, namely to split an opinion into two separate opinions which when fused would produce the original opinion. Different fusion methods can be applied, depending on the situation to be modelled. The cumulative fusion operator and the averaging fusion operator are defined for subjective opinions, and for belief functions in general. This paper describes fission of opinions which is the opposite of cumulative fusion. The fission operator can for example be applied to transforming trust networks with dependent trust paths into trust networks in canonical form where all trust paths are independent.